A transparent conductor permits the transmission of light while providing a conductive path for an electric current to flow through a device including the transparent conductor. Traditionally, a transparent conductor is formed as a coating of a doped metal oxide, such as tin-doped indium oxide (or ITO), which is disposed on top of a glass or plastic substrate. ITO coatings are typically formed through the use of a dry process, such as through the use of specialized physical vapor deposition (e.g., sputtering) or specialized chemical vapor deposition techniques. The resulting coating can exhibit good electrical conductivity. However, drawbacks to techniques for forming ITO coatings include high cost, high process complexity, intensive energy requirements, high capital expenditures for equipment, and poor productivity.
For some applications, patterning of a transparent conductor is desirable to form conductive traces and non-conductive gaps between the traces. In the case of ITO coatings, patterning is typically accomplished via photolithography. However, removing material via photolithography and related masking and etching processes further exacerbate the process complexity, the energy requirements, the capital expenditures, and the poor productivity for forming ITO-based transparent conductors. Also, low visibility of patterned transparent conductors is desirable for certain applications, such as touch screens. Conventional patterning techniques for ITO coatings typically result in patterns that are visible to the eye, which can be undesirable for those applications.
It is against this background that a need arose to develop the transparent conductors and related manufacturing methods described herein.